The long-term goal of this pilot project is to develop a comprehensive research resource to: a) study genetic predispositions and environmental interactions in lung cancer etiology, and b) foster methods for identification of individuals at high risk for lung cancer. Specifically, we propose to develop a family panel data base ascertained through incident cases of lung cancer seen at the Johns Hopkins Hospital. We will characterize index cases with respect to family history and environmental risk factors, including smoking, collected by questionnaire/interview. Blood samples on available family members will be obtained, and a database of accessible family members will be developed for future physiologic, biomarker, and molecular genetic studies by other projects within the SPORE. Within the pilot study, we will use two approaches to analyze the data that we collect: 1) Segregation analysis using regressive logistic models will be performed on the obtained pedigrees to estimate the genetic and environmental contributions to lung cancer risk considering age at onset; and 2) Affected relative pairs from the family panel will be studied to test the hypothesis of concordance of tumor histology (SCLC vs non- SCLC).